The aim of this study is to evaluate the metabolic effects of prostaglandin E1 administration in patients with liver cirrhosis and paired healthy controls. The hypotheses being tested are: 1) Prostglandin E1 significantly influences hepatic and whole body amino nitrogen economy in patients with liver cirrhosis; 2) Prostaglandin E1 produces a decrease in urea synthesis, and 3) Prostaglandin E1 might act on the peripheral tissues, through a decreased amino acid efflux, or increased amino-acid uptake and non-oxidative metabolism. To date 4 subjects have been enrolled. No data analysis has been done.